Portable power cut-off saw



Dec. 11 1923.

' T. FINLJ'AYSON PDRTABLE POWER CUT-OFF SAW Filed Feb. 25. 1920 2 Sheets-Sheet 1 Du "c7 fan.

Dec; 11 1923.

T. FINLAYSON PORTABLE POWER CUT-OFF SAW Filed Feb. 25. 1920 2 Sheets-Sheet 2 l h. w Q Hm") u E.

Patented Dec. 11, 1923.

THOMAS FINLAYSON', OF OAKLAND, CALIFORNIA.

FHQ.

PORTABLE POWER CUT OFF SAW.

Application filed February 25, 1920. Serial No. 361,316

new and useful Improvements in Portable Power Cut--Ofi' Saws; and I do hereby declare the following to be a full, clear, and exact description of the same reference be ing had to the accompanying drawings, forming part of this specification.

This invention-relates to saws of medium size for cutting up logs and beams or for felling'standing timber of a size up to two feet in diameter, and has for its object the provision of a saw of this nature which will enable one man to accomplish with it the work of at least two men and in a slightly more expedient manner. 7 The invention contemplates the provision of a readily adjustable saw driven by a high speed engine having a relatively short stroke, and has for its principal object the provision of means for simplifying and improving saws of this nature.

WVhile there are a number of portable power saws on the market most of them are entirely too complicated for use or else are too cumbersome to be operated by one man so that where labor is at high price little can be gained by the use of such style power saws, because the time gained in sawing as against the time required when using a simple cross cut saw is more than lost by the time necessary to adjust the machinery. In the present case however, the saw and the clamp are separate pieces and the clamp can be adjusted to a nicety with great ease and insures the location of the kerf at the exact point desired, since the space between the line of the saw teeth and the edge of the clamp is a definitely fixed distance One notable improvement of the present device over other saws is that in cutting a piece of wood lying flat on the earth it is possible to saw right down to the ground without block-. ing up the timber to be sawed.

Referring now to the drawings: Y

Fig. 1 is an elevation of my device at the end of the sawing operation. a

Fig. 2 is a plan view thereof.

Fig. 3 is a side elevation of the clamp.

Fig. 4 is an end elevation of the complete device taken from the motor end.

Fig. 5 is an end elevation taken from the opposite or free end of the device.

Fig. 6 is a perspective view of the bracket at the end ofthe saw support.

The device in its preferred trated in the drawings consists of three principal partsthe clamp, the engine and the saw, these parts being readily assembled by means of an axle 10 which passes through a cylinder 11 at the end of the saw support, through a thimble bearing 12 integral with the engine frame, and also through a sleeve 14 integral with and forming one end of the form as illusclamp. Referring particularly to Figure 3, l i

the clamp consists of but two parts or aws,

- one a casting 15 and the other a foot 16, the

latter provided with slots 17 to receive the guide rods 18 which are integral parts of the other jaw 15 which may be considered as the permanent jaw of the clamp, since the foot or movable jaw 16 is the adjustable part thereof, receiving its motion by virtue of a threaded engagement with the adjusting screw 20 journaled in a yoke 21 and having a bevel gear 22 meshing with a similar but larger gear 23 on the shaft 24. which latter is journaled in the, arms 25 of the yoke 21 and is operated'manually by means of a crank handle 27 thereby causingthe footpiece 16to move toward or away from the stationary jaw 15 according to the direction ofrotation of the shaft 24. The engaging face 30 of the movable 16 is preferably provided with small prongs or spikes 31 to securely grasp the timber to be sawed and is of such length as to he most convenientfor use with the type of material intended to be operated upon.

The casting 1.5 is provided at one end with a shelf 34adapted to overlie one edge of a square piece of timber, as best shown in Fig ure 3, and at the other end carries the sleeve 14 which as has been stated is an extended cylinder forming the main support for the engine and the saw frame. The sleeve 14 is connected to the engaging face 36, which as shown in Fig. 3 is a vertical continuation of the horizontal shelf 34 by means of, a plate 37 reinforced above and below With the usual stiffening ribs 38 which are preferably alined with the guide rods 18, although not necessarily so. The casting 15 also carries on the side nearest the saw support a laterally extended web 40 having at its end a flange guide 4-1 provided at two or more places with L-shaped lugs 1-2 for cooperating therewithto' form a guideivay for the arc extending from oneot the'side pieces 48 of the saw support.

The saw support consists principally of the side pieces 48 and 49' which are in general of U-shaped formationand extend parallel to one another in their central portion, but are extended outwardly as at 50 atthe front end and also diverge at that point to form a saddle 51 cooperating with a cap, 52 to form abearing for the guide rod- 53 of the saw frame 54:. At the rear end these side pieces 48 and 49-again diverge as: at 56 for a similar purpose and are extended at a sharp angle to the leg of the U in a bracketlike formation, holding in place the cylinder 11 which surrounds the axle: 10. At a central point the cylinder 11 has mounted in lugs thereon axsma-ll cog wheel 60 operated by a handle 61 for quickly projecting-the axle 10 through the sleeve 14; and'into the thimble bearing 12 when'it is desired :to lock the three principal parts of the device together. The bearing 62 for the rear gulfle rod 63 is hushed-in the usual manner as. is also the bearing for the front guide rod 53. The saw frame 54L is of the normal U-shaped formation and as has been previously men tioned carries the two guide rods and 63, and below these'rods is provided with the usual fixed fastening means 66 and the mating-adjusting means 67 the latter being operated by the thumb-nut 68 to tighten up the-(saw blade 69 which is made of a fine quality high speed steel in orderto stand the heavy duty imposed upon 1t by the rapid work. The frame 5t'is-providcd at 1tscentral portion with a slot 70 receiving therein a small wheel 71 mounted on an axleTQ sup ported in the side-pieces 4:8 and 49'to partly carry the weight of the saw and partly to lessen the friction. v

The motor may be of any desired type, but as illustrated, consists of acoinprcssed air engine having four cylinde1.'s,--two of which 75 are arranged vertically :mdt'ne other two '76 arranged horizontally thus providing a very compact arrangement of angle engine well adapted for this type of work.

v The power shaft 77 of the motor may be directly connected to the saw by means 01" the usual crank but for certain SlZQS of apparatus 1 preferably insert a gear 78 between ing as the saw blade is from such edge when assembled, and when this position has been ascertained. the clamp-is-fastenedin place thus secured the engine and saw support are so located with respect to-reach other that the are 45, of the support: will lit in the groove of the guide 4]. which will hold the parts in position sufficiently long to insert the axle 10 through the "sleeve 14; and into the thimblecl2, such movement bcin w accomplished by a coupleof turns or. the handle 61 operating thegear 60v meshing with the rack- 81 shownin Figure 6. The device is nowready to startsawing and this is accomplished by turning. thesaw oni-the axle 10 by meansofthe handle 825which is the admission pipe conveying compressed air to the engine and is provided asusual with the regulation. lever valve 88 for controlling the pressure and. also with the spring-pressed; admisslon valve 84 in. close proximity to the knurled handle: portion 84 connected-to the flexible-hose 85. The saw starts its kerf atthe corner of the block engaged by the shelf 34 and ends the, stroke parallel to the face of such a block as shown in Figure 1.

What isclaimed is 1. In a device of the character described aclamp, a sleeve carried by said clamp, an

axle in said sleeve, a sawv support pivotally mounted on said axle, and means carried by said sawsupport for removing said axle tromisaid sleeve. a

2. In a .deviceof the character described,

clamp consisting: of a. fixedjaw and amovable jaw adjustable. with respect thereto, a bracket extending from said fixed jaw, a sleeve at the end oflsaid bracket, an axle slidably mounted insaid' sleeve, a saw support, plurality of spaced coaxial hollow cylinders carried by said saw support. and adapted to slidably receive said axle, a saw carried by Said saw support, means romeciprocating said saw, and means carriedby one of said hollow cylinders for sliding-said axle in andiout of said sleeve.

3.- In a device of thecharacterdescribed a clamp, a saw support pivotally, mounted thereon, said sawsupport consisting 'ofitwo spaced parallel Usshapedlmembers, an antifriction wheel centrally; mounted between said members, a savvmounted between said members and supported in part. by said anti-friction wheel, and means ton reciproeating said. saw. v

4. In a device of the character described, a clamp consisting of a fixed and a'movable jaw adjustable with relation thereto, a bracket extending from said fixed jaw, a sleeve on the end of said bracket, an'axle in said sleeve, a saw support pivotally mounted on said axle, said support consisting of two approximately parallel U-shaped members, a friction wheel mounted between said members, a saw mounted between said members and having a bearing rod at either end slidable in bearings provided by said U-shaped members and guided centrally by said friction wheel, and means for reciprocating said saw.

5. In a device of the character described, an adjustable clamp, a saw support, a reciprocating saw, means for operatin said saw, and a single means for assembling the saw support, clamp, and operating means to provide for pivotal movement of said saw, said support and said operating means.

6. In a saw support, a reciprocating saw, a plurality of U-sha ed members substantially parallel throug iout their central POI? tion but extended outwardly from the U-portion and divergent at said point of departure to provide bearings for said saw, additional means for guiding the central portion of said saw, means'for reciprocating said saw, and means for pivotally mounting said saw and support with respect to the material to be sawed.

7. In a device of the character described,

an adjustable clamp, a saw support pivotally mounted on said clamp, co-operating means on said clamp and said support for guiding said saw support in its pivotal movement, and rack and pinion meanscarried'by said support for quickly disconnecting said-support from said clamp. v

THOMAS FINLAYSON. i 

